The present disclosure relates in general to communication between electronic devices and in particular to communicating sensor data between two electronic devices, such as a computing device and an accessory.
Mobile computing devices, including smart phones, personal digital assistants, and tablet computers, are rapidly becoming ubiquitous. Such devices often include sensors that provide information about the device or its surroundings, such as ambient light sensors, proximity sensors, accelerometers, magnetometers, and so on. These sensors can produce a continuous stream of data, which is typically sampled by a processor within the device and used in various ways. For example, data from an ambient light sensor can be used to automatically brighten or dim the device's display. Accelerometer data can be used to automatically rotate the display based on which edge is currently pointed up. Magnetometer data can be used to infer orientation of the device (e.g., a compass direction), and this information can be used in navigation or other applications.
Some mobile computing devices can also communicate with “accessory” devices, such as speakers and/or video systems that can receive video content from the mobile computing device, remote control devices, and the like. The mobile computing device can, for example, stream media content (e.g., audio and/or video) to the accessory or receive control signals from the accessory to control playback, communication, or other operations.